Electronic
Hybrid and MIDI Controllers
The
LightHarp MIDI Controller and Digital Serpent [Serpentine Bassoon]
© copyright
Bent Leather Band all rights reserved 2004.
Serpent
The Serpentine Bassoon is a
unique Australian double-reed instrument constructed from a 2.6
meter leather tube [the equivalent length of a bassoon]. This
conical bore instrument was designed and built by Garry Greenwood
specifically for and in collaboration with Joanne Cannon.
Leather is a flexible material, allowing
itself to be looped and curved to achieve a playable shape. Unlike
the instrument's early music equivalent; the serpent [an instrument
constructed from wood and then covered with leather], the serpentine
bassoon is constructed from two sheets of polished leather; providing
a good acoustically reflective surface inside and out. The leather
tube is then wet-formed into the specific shape and heat dried.
Leather is less resonant in comparison to other acoustic materials.
This facilitates amplification without the usual worries of screeching
feedback tones.
The Serpentine Bassoon is played with
a normal bassoon crook and double reed. Joanne, however has carefully
modified the instrument by including microphones [pickups], a
touch sensitive thumb-plate, pressure and movement sensors, which
the musician can use to control synthesisers, samplers and effects
machines. Joanne uses the instrument to produce an incredible
wide range of sounds;including wild animal cries, soft-detailed
plucking sounds, bassoon, horn and oboe timbres, cycling rampaging
flangers, distortion tones, melodic shifting delays and echoes
and all manner of bizarre oscillations, sirens, mutterings and
warbling.
LightHarp
The LightHarp uses spotlights,
lasers and light sensors to trace virtual strings through space
for performers to play. The instrument does not make sound itself
but rather it controls computers and synthesisers in performance.
The instrument was originally built in fiberglas and designed
by violin and instrument maker David S. Brown in collaboration
with Stuart Favilla and Robin Whittle [a notable computer music
instrument developer and designer]. The current LightHarp has
been designed and constructed in leather by world renown, Tasmanian
leather artist, Garry Greenwood.
The LightHarp is also the World's
first Indian computer music instrument and resembles a veena in
shape and iconographic design. Dragons [yali] have long been used
as motifs in the decorative design of Indian and Asian musical
instruments. The LightHarp resembles the Indian Makara with its
sea-serpent like design but also takes many structural and aesthetic
ideas from the contemporary veena. Included in these is the symbolic
representation of the human body where the base or gourd of the
instrument represents the pelvis while the instrument's neck and
sensors [frets] symbolize the spinal column and vertebrae. Trumpets
and flutes have often adorned Indian instruments in the past,
the LightHarp's horn makes no sound however.
The LightHarp has a total of 32
light-sensor virtual strings. These strings can play separate
notes, individual samples or function as frets on a single string.
A schmitt-trigger mechanism greatly improves the response time
of the sensors and reduces onset delays to less than one millisecond.
The thresh-holds of the schmitt-triggers can be attenuated to
turn specific strings on/off. This allows for the performance
of modal glissandi for ragas and Asian scales. Although the LightHarp
was designed for Indian music, it is also capable of performing
uniquely rich and dense abstract synthesis textures and experimental
micro-tonal tunings.
The 32 strings are transposable
over eight octaves and tuning to various scales and paradigms
is controlled through the use of the ancillary controllers. The
ancillary control panel consists of 24 simultaneous channels of
scanning analogue to digital control capable of hundreds of MIDI
controller assignments. The main controllers include breath-control,
a pitch and modulation joystick, pressure sensitive and position-sensitive
touch strips, foot-control pedals, two large dial controllers
[that operate concentric to each other] and an active electromagnetic
proximity controller wand. The instrument is usually played with
5 independent degrees of freedom. In addition to these controllers
the LightHarp also has mounted parameter control mixer based on
the MIDIBox plus freeware circuit available from German hardware
designer Torsten Klose. The MIDIBox plus allows for sixteen dials
to control up to 760 parameters during performance.
Installations
Working with lasers we have
created many large scale LaserHarp works. Originally, these works
were created for dancers and lasers were used to trigger samples
and other sounds. Since 1993, we have created works for public
installations, performances, workshops, concert performances and
exhibitions. Since 2000 the work has become integrated with our
live performance work.
Our installations provide a spatial
mapping system that controls interactive performers, [computer
based performing algorithms]. We use these algorithms to provide
other accompanying parts to our live performance. Laser strings
can be traced over huge distances. Although this creates spectacular
visual effects it also creates problems in regards to focusing
and tracking lasers to their respective sensors. Vibrations and
wobbles can affect beam shifts easily over long distances and
targeting is a nightmare. Joanne Cannon has developed systems
for mounting and aiming lasers, [pictured right]. Together with
sensor stands that are equipped with 60 mm lenses. Accurate tracking
of lasers and sensors, has been achieved over distances of up
to one hundred meters.
The interactive space is further
enhanced with theremins, pressure sensitive mats and voice-tracking.
Voice-tracking [machine-listening] provides our composing and
accompanying algorithms with a constant stream of information.
The computer responds, inverting, retrograding, harmonizing, etc.
The respondent pitch stream is then fed to other algorithms that
perform the stream in a musical way. These algorithms add gesture,
life and performance nuance. Various setups of algorithm parameters
are then saved to specific areas of the installation for either
the performers or audience to play.
Within an improvised music setting,
this interactive process allows the musician a moment for reflection
and an opportunity to push beyond the self-imposed direction of
the improvised stream. This achieves a musical result that sounds
both spontaneous and highly organized. Form is governed both by
the improvisation and the position of the player/s within the
installation space.
Active electromagnetic wands are
also used which work on a similar principle to theremins. However,
our EMG controllers are tuned to resonate at specific frequencies
so that multiple wands can be used all within the same space without
causing any interference with each other. These controllers are
scanned at much higher rates than popular ultrasound controllers,
which usually have to scan very slowly in order to compensate
for acoustic reflections.
